1. Field of the Invention
The present invention relates to an endoscope apparatus including a bendable bending tube to be provided on a distal end side of an inserting section.
2. Description of the Related Art
An endoscope apparatus to be inserted through a body cavity or a lumen for observing insides is generally known. An inserting section of an endoscope apparatus to be inserted through a body cavity or the like is configured to have a distal end portion that is freely bendable to move forward and backward along a bend in the body cavity, or to pick up an image of a part to be observed. The bending portion has a configuration in which a plurality of short bending pieces are jointed.
The bending pieces are connected to one another by wires, and can be freely bent by adjusting traction and relaxation of the wires by operating an angle knob of an operation section provided on a proximal end side.
When producing a bending portion, because of improvements in processing techniques, a link portion to be a rotation shaft of a joint portion and an engagement portion are simultaneously produced by making cuts in a straight tube with laser light. For example, Patent Literature 1: Japanese Patent No. 2944533 proposes a technique for making cuts in a straight tube with laser light toward a nearly central axis from a periphery of the tube, thereby forming bending pieces that are jointed to constitute a bending portion.